1. Field of the Invention
The present invention relates to a thin-film transistor device of a liquid crystal display.
2. The Related Arts
In a currently available design of a thin-film transistor used in a large-sized thin-film transistor liquid crystal display (TFT-LCD) where a source terminal and a drain terminal are arranged to be parallel to and in alignment with each other, the thin-film transistor comprises a gate terminal (not shown), a source terminal 20, and a drain terminal 40. Referring to FIG. 1, the source terminal 20 and the drain terminal 40 are arranged side by side and above the gate terminal and edges of the source terminal 20 and the drain terminal 40 that oppose each other are parallel to each other. In other words, a straight channel 60 is formed between the source terminal 20 and the drain terminal 40. A channel 60 formed between the source terminal 20 and the drain terminal 40 is a semipermeable film structure. The areas of the source terminal 20 and the drain terminal 40 are completely non-light-transmitting, while the channel 60 is partly light transmitting. The channel 60 comprises a channel width W and a channel length L. Irradiation of light is made on opposite sides of the channel. Since the light receiving areas at the two ends of the channel are greater than the middle, after exposure, photoresist at the two ends are removed and a curved configuration is formed, as shown in FIG. 2. Under this condition, the channel width W of the channel 60 is reduced and charging rate of the thin-film transistor is affected. At the worst, the channel 60 may be broken through, namely the channel width W becomes zero. This becomes open-circuiting, totally ruin the thin-film transistor.